Transplantation of microencapsulated rabbit schwann cells in rats after spinal cord injury: Basic fibroblast growth factor expression and hindlimb movement function changes / 中国组织工程研究

ABSTRACT

BACKGROUND: Transplantation of microencapsulated rabbit Schwann cells in the rat spinal cord can relieve inflammatory reaction, promote spinal cord regeneration, but the precise mechanisms remain unclear. OBJECTIVE:To observe basic fibroblast growth factor (bFGF)expression and movements recovery following transplantation of microencapsulated rabbit Schwann cells in rat spinal cord. METHODS: The sciatic nerves taken out from rabbits wore digested with mixed enzyme and were made into Schwann cells suspension. Then we used air-jet method to make Schwann cells microcapsule. Using the same method, empty microcapsule was made. Sprague Dawiey rats were randomly divided into cell group, empty microcapsule group and microcapsule group. Conducted by hemisection injury of spinal cord,the rats in cell group,empty microcapsule group and microcapsule group were implanted with gelatin sponge with 10μL Schwann cells suspension, gelatin sponge with 10 μL empty microcapsule and 10 μL microencapsulated Schwann cells. Normal group was left intact. After operation, we observed hindlimb movements recovery in rats with the Basso, Beattie, and Bresnahan (BBB) scale. Meanwhile,a set of sections were stained immunohistochemically for bFGF expression, another set of sections wore stained for hematoxylin-eosin and Nissal. RESULTS AND CONCLUSION: After spinal cord injury, rat right hindlimb affected paralysis immediately. At 7, 14 and 28 daysfollowing transplantation,motor function in rat hindlimb was significantly recovered, and the BBB scores were significantly higher in microencapsulated schwenn cells than in cell and empty microcapsule group (P < 0.05 or P < 0.01). bFGF positive products were mainly distributed in cytoplasm of the spinal neuron and nucleus of neuroglical cell. The numbers of bFGF positive glial cells mainly appeared surrounding the spinal cord injured site on days 1, 3, 7 and rose to its peak on day 3 and began to appear in neuronal calls on day 14. The number of bFGF positiv cells in microcapsule group was significantly superior to that in cell group and empty microcapsule group. From then on, the bFGF expreSsion was significantly decreased in each group. These indicated that transplantation of microencapsulated Schwann cells can inhibit the immunological rejection after xenotransplantation, suppress inflammatory reaction, improve the expression of bFGF, increase hindlimb movements recovery and spinal cord regeneration after spinal cord injury.